Question: Simplify the following expression: $k = \dfrac{10r - 8s}{12s + 2r} + \dfrac{4r}{12s + 2r}$ You can assume $r,s,t \neq 0$.
Solution: Since the expressions have the same denominator we simply combine the numerators: $k = \dfrac{10r - 8s + 4r}{12s + 2r}$ $k = \dfrac{14r - 8s}{12s + 2r}$ The numerator and denominator have a common factor of $2$, so we can simplify $k = \dfrac{7r - 4s}{6s + r}$